We were contracted by ATX many years ago to clean up a another dealers installation  when more than half of the customer systems were reported as inoperative by the customer. The unit were the early product versions fitted with the large Hard Drives for storage that offered massive storage capacity at the cost of reliability. Aside from mounting the units on their side, the installer failed to secure the lock box properly and when the fragile mounting system failed it permitted the lock box and DVR to smack back and forth with every acceleration and braking inertia, with a full 3" swing span permitting more than enough G force to destroy almost every Hard Drive mounted in this fashion in short time.The best value in school bus video or vehicle camera systems is the 100% solid state SD4m or SD4.